11. Omfori Island — €50 million (£36 million, $55 million).

This partially developed island has only one building: the one you see in the picture. It does, however, have planning permission for someone to build on 20% of the island. Private Islands Online says in the prospectus that if the buyer can prove that it is a good investment to build more properties on the island, the Greek government is likely to grant further permission.

10. Dulichium Island — €40 million (£28.4 million, $44.1 million).

This is the largest private island for sale in Greece right now. The highest point on the island is 250 metres above sea level. It has about 4,000 olive trees, shrubs, and dwarf bushes. It is undeveloped but presents an opportunity for someone to turn it in a luxury-hotel resort.

This island is only half an hour away, by speedboat, from Athens. Numerous international developers are already showing an interest, according to Private Islands Online, because of the island's close proximity to the Greek capital.

8. St. Thomas — €15 million (£10.7 million, $16.5 million).

St. Thomas Island is only 20 minutes away by water taxi from Corinth in Greece and only 45 minutes away from Athens. It is also part of the Diapori chain in the Saronicos Gulf, "an area of Greece mythologized for the lush emerald beauty of its picturesque islands."

7. Nafsika Island — €6.9 million (£4.9 million, $7.6 million).

Nafsika Island was recently sold but still features on the Private Islands Online website. This mountainous island is one of the last undeveloped spots within the Ionian Sea and has sheltered bays, three large natural harbours, and high vantage points with 360-degree views.

6. Kardiotissa Island — €6.5 million (£4.6 million, $7.2 million).

This large property in the heart of the Aegean Sea has incredible transport links and is touted as a perfect place to set up facilities for sailing, diving, and adventure sports.

Private Islands Online points out that the island is between Folegandros and Sikinos, which are both under 10 minutes away by speedboat. There is also a daily all-year-round link with ferries to Piraeus from both islands.

5. Nissos Sofia — €5.5 million (£3.9 million, $6 million).

The island is owned by a private individual and was designated as a Ramsar site, meaning it is a wetlands of international importance. This means the area is guaranteed to have a high level of privacy because commercial boats are restricted from sailing in the waters.

4. Kythnos Island parcel — €5 million (£3.6 million, $5.5 million).

This island is just an hour from Athens by boat and is already inhabited with 20 to 25 picturesque small houses. It is also only leasehold, meaning ground rent will have to be paid to the owner of the land. But because it is developed, roads, building, and local culture are ready to be given a boost by land development.

3. Stroggilo Island — €4.5 million (£3.2 million, $5 million).

This 54-acre island is in close proximity of the popular island of Marathos, in the Aegean Sea.

Though the island is nondeveloped, Private Islands Online points out that the water can become drinkable with a small filtration processer, and it is able to derive electricity from Marathos, which has an established power grid.

2. Isle of Gaia — €3 million (£2.1 million, $3.3 million).

This is dubbed the "millionaires' playground" by Private Islands Online because of its clear ownership by a private company that has approval to build six villas and permission to subdivide into six plots. The region is also touted as having idyllic conditions for water sports, sailing, fishing, deep sea diving, and swimming.

The bonus — it costs less than than buying a house in some upmarket parts of London.